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> alternator dead, sigh...
bd1308
post Dec 30 2005, 01:46 PM
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so i get a flickering glowing light (gen light) and is this possible to change out with the engine in the car? i get *NO* usability from this alternator.

or can i fix it?

b
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McMark
post Dec 30 2005, 01:55 PM
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The alternator can be changed with the motor in the car. Not fun the first time, but gets easier each time. I think I can do them in about an hour now, took me about four the first time. (IMG:http://www.914world.com/bbs2/html/emoticons/wacko.gif)
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John
post Dec 30 2005, 01:55 PM
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I am very sorry to hear that your alternator is bad.

Have you tried plugging the Voltage regulator directly into the harness? (I have heard that the relay boards can act up)

I have changed one in a car once and it was a PITA.

I don't know that I would suggest to anyone to try. I just know it can be done. There isn't much room in there to do it .

If you attempt this I forsee several scrapes and many many choice curse words....
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lapuwali
post Dec 30 2005, 02:02 PM
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Plugging the alternator harness directly into the VR means there's no connection the G light anymore, so no field current, so no charging current. You'd have to connect the blue wire at the relay board directly to the D+ on the VR or the alternator.

bd, your problem could be wiring or the VR as well as the alternator.
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Mueller
post Dec 30 2005, 02:02 PM
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as long as the windings are not open (good chance they are fine), and if you can get the parts to repair it, then yes, you can rebuild them....

here is a decent article on the subject, I'd think there are more on the web if you search enough.....

rebuilding Bosch Alt.


(IMG:http://www.humanspeakers.com/audi/images/alternator.jpg)
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bd1308
post Dec 30 2005, 02:21 PM
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really strange.

so i plug the VR into the alternator. My first thought is that hmm, isnt that bootstrap circuit supposed to be with it? No light when i turn the key. no light when i rev it a tad to "boot" the alternator. check volatge, right on 12.20-12.25V. pop headlights, and rev to 2500RPM and wait....12.2, 12.10, 12.00, 11.93, then pops back up to 12.1V

b
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bd1308
post Dec 30 2005, 02:30 PM
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well...i think this alternator is toast. Let me try the harness again and some other things to see what's going on. But i think that the alternator has said its final goodbye.

b
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Mueller
post Dec 30 2005, 02:58 PM
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QUOTE (bd1308 @ Dec 30 2005, 01:30 PM)
well...i think this alternator is toast. Let me try the harness again and some other things to see what's going on. But i think that the alternator has said its final goodbye.

b

you are giving up too easily (IMG:http://www.914world.com/bbs2/html/emoticons/wacko.gif)

read this article 914 alt. troubleshooting

basicly, jump a 12vdc + from the battery to the alt. > start motor > if you have voltage output from the alt. more than 12vdc (should be 14 to 16) then good chance it's your wiring or voltage regulator

I've had voltage regulators die on me before and as a temp solution (very temp) you can wire the alt. to produce max voltage using the DF (field) terminal


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Cap'n Krusty
post Dec 30 2005, 03:01 PM
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With everything in place, does the light illuminate when you turn on the key? Have you cleaned and checked the fuses? Does the light extinguish when you start the car and exceed 1500 RPM? Are you measuring the voltage across the battery posts? If you're checking it by the gauge, you're asking for trouble. It measures the voltage at or near the fusebox, and is notoriously "eye candy". If you decide (after answering these questions), buy a voltage regulator first. Get a real Bosch one; the others don't work, more often than not. If that doesn't solve the problem, get a genuine Bosch reman alternator. Mind the length of the post on the back. It can short out against the rear cover. The Cap'n
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rhodyguy
post Dec 30 2005, 03:21 PM
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britt, is this going on (the light) at idle and only when the lights are on? my idle falls way off with the lights, wipers, stereo, etc are on and then alt alt light will flicker.

k
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r_towle
post Dec 30 2005, 06:05 PM
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for an engineering student, you jump to conclusions way to quickly....

You need to be more methodical...

It is cheaper to be methodical...

Lets review....
Your alternator was ok before you changed the wiring and added new crap to the relay board...right

It was ok and working before you took out the voltage regulator to remove the cover to the relay board, right...

If it was me, and I am cheap, I would be cleaning and re-seating all those cables, and make sure to apply pressure to the bottom of the relay board while you are pushing down so you dont break something else....

Check your alternator correctly.
bypass and check your voltage regulator (I vote for dirty contacts and not seated correctly)

Check your voltage output at the battery while at 2500 rpms STEADY, not blipped.

Fill your battery with new water, and charge it fully with a battery charger before jumping into a new alternator.

Be thorough, its cheaper.
Rule out everything you did first, since this problem happened (HHMMM New Ljet FI wiring...)

Rich
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lapuwali
post Dec 30 2005, 09:44 PM
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If you plug the VR directly into the alternator harness IT WON'T WORK! You MUST run the blue field wire to D+. If the light doesn't come on with the key (engine off), then you will NOT have an operating charging system with the engine running.

Voltage at the battery terminals while the charging system is working should be closer to 14v, not 12.5v. If it's lower than 13v, then the charging system isn't working, and you're running straight off the battery, which is why you saw continually declining voltage.

The VR AND the alternator AND the wiring all have to be good for the charging system to function. An inoperative charging system can be caused by ANY of those being wrong, not just the alternator.

I agree with Rich, this is most likely a wiring problem, since that's what you've been messing with. The odds are good both the VR and the alternator are fine.


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John
post Dec 30 2005, 10:01 PM
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QUOTE
Have you tried plugging the Voltage regulator directly into the harness? (I have heard that the relay boards can act up)


I don't know what I was thinking when I wrote that.

Of course, this won't work without the exciter circuit hooked up to energize the field...... (OK, I'm a dumbass)
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bd1308
post Dec 30 2005, 11:15 PM
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okay. I was thinking about this while I was driving (AAA card in my wallet) and the cable I did mess with was the starter cable...the HUGE 8GUAGE cable. Im going to strip it down to good metal and seat it in my little positive lug connector.

b
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SLITS
post Dec 30 2005, 11:38 PM
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3 wires to the starter:

One from battery

One from alternator

Both go on the top lug of the solenoid

One spade terminal wire

Goes to spade terminal of solenoid.
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bd1308
post Dec 30 2005, 11:49 PM
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teh light flickers, intermittent connection. If i clean the connections up, it'll work fine IMHO.

sorry for the scare guys.

b
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Tom Perso
post Dec 31 2005, 07:02 AM
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Glad you didn't buy an alternator?

LOL

Engineer = CSOB - First lesson in being an engineer.

Happy New Year!
Tom
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davep
post Dec 31 2005, 07:12 AM
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Also check the ground leads from the tranny to the trunk floor and the body to the battery. While these are most important during starting, they are always in the charging circuit. What I liked to do was to put a ground lead from the battery to the fan shroud; that improved one car dramatically.
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bd1308
post Dec 31 2005, 08:38 AM
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already done friend.

right now, the battery lug connector thing has a compression fitting that I messed with when I put on the Dual relay 12V connection.

so i think that's what my problem is.

b
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bd1308
post Dec 31 2005, 09:41 AM
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well this thing is getting really out of hand.

I can't understand for the life of me why this car wont start.

b
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